Hydrocarbons, such as oil and gas, are commonly obtained from subterranean formations that may be located onshore or offshore. The development of subterranean operations and the processes involved in removing hydrocarbons from a subterranean formation typically include a number of different steps such as, for example, drilling a wellbore at a desired well site, treating the wellbore to optimize production of hydrocarbons, and performing the necessary steps to produce and process the hydrocarbons from the subterranean formation.
The steps of completing the well, including well stimulation, well enhancement, zonal isolation, sand control, and other completion steps often use tubular downhole tools to perform a variety of functions. These downhole tools are often operated with a ball or plug. The plug or ball lands and seals on a sleeve or seat internal to the tool, allowing pressure to be generated. The pressure build up enables the sleeve or seat to slide from one position to another position. The sleeve or seat can thus move from a closed position to an open position, whereby casing ports are opened, thus allowing fluids to flow into the annulus or subterranean formation. Downhole plugs are a fairly simple and generally reliable means of activating downhole tools.
One of the drawbacks of downhole plugs, however, is that after a particular downhole operation has been performed, the plug needs to be moved out of the way to continue operations. One technique for doing this involves drilling the plug out of the downhole tool. Another technique involves pumping fluid downhole at such a high pressure that the plug is forced down and sometimes out of the downhole tool.
Recent develops have led to efforts to optimize the use of the downhole plugs, for example, by reusing them in subsequent wellbore operations. Such efforts include designing the seats that the plugs set into to shear at high pressures. This enables the plugs to travel downhole for subsequent use. This solution, however, is less than optimal because there are a number of restrictions within the casing, including the inner diameter of the casing itself and coupling transitions, which can interfere with the dislodged seats.
The present disclosure is directed to a multi-function plug, which includes a detachable member, which enables the plug to engage with at least two seats to perform at least two separate downhole operations. By employing a detachable member, the plug have a reduced outer diameter, which enables to continue downhole with minimal chance of forming an obstruction.